Between animal and human medicine, there is no dividing line-nor should there be.

Life itself is but the expression of a sum of phenomena, each of which follows the ordinary physical and chemical laws.

Belief cannot be reckoned with in terms of science, for science and faith are mutually exclusive.

Marriages are not normally made to avoid having children.

As long as vitalism and spiritualism are open questions so long will the gateway of science be open to mysticism.

Medicine is a social science, and politics is nothing more than medicine on a grand scale.

The task of science, therefore, is not to attack the objects of faith, but to establish the limits beyond which knowledge cannot go and found a unified self-consciousness within these limits.